If it is new you dont get a test cert.
Instead the "tested until date" is stamped on the cylinder - assuming it is steel, dont know what they do with carbon. On mine it is a MMYY format and valid 3 yrs from mrf (not purchase).
After that you test. If you mark the cyl as "for on-shore use only" you can get a 5 year instead of a 3 year cert I believe.